The present invention relates to an apparatus and method of brain therapy using neurofeedback, and in particular to an improved method and apparatus for low energy neurofeedback.
Generally speaking, neurofeedback is a method of treating physical or psychological disorders having some form of organic brain dysfunction. Various methodologies involve recording the brain electrical activity from pattern of electrical leads placed on and around the scalp, known as an electroencephalograph or EEG.
The EEG reveals periodic variations in electrical activity within the brain, which has traditionally been characterized as combinations of four frequency bands or components; which are delta, theta, alpha, and beta. While the state of consciousness is the primary cause of one frequency being dominant over the other, subtle variations in these components frequently indicate underlying disorders. During sleep, delta waves having a frequency of four hertz (Hz) are dominant. Theta waves (4 to 8 Hz) are associated with the twilight consciousness on the brink of sleep, during which dreamlike mental images can surface. At higher frequency still are alpha (8 to 12 Hz), which are dominant in the calm and mentally unfocused state typically connected with relaxation. Beta waves, from 12 to 35 Hz are dominant in the normal waking state, when our eyes are open and focused on the world. When the patient is relaxed but alert the beta waves tend to be at the lower frequency range of 12 to 15 Hz, whereas in the excited, anxious state the beta waves can be as high as 35 Hz. Early EEG neurofeedback focused on helping people learn to generate waves associated with deep relaxation: alpha and theta. Other treatment modalities evolved in which the patient received a stimulus based on the results of the EEG.
Although neurofeedback modifies the brain function in a manner not fully understood, such treatments are now well correlated with therapeutic benefits for many types of disorders. Further, changes in a patient's EEG can also reveals that the brain function is modified by the feedback.
One such method is more fully described in U.S. Pat. No. 5,365,939 (issued to Ochs on No. 22, 1994), and U.S. Pat. No. 5,036,858 (issued to Carter et al. on Aug. 6, 1991 and re-issued as RE 36,348 on Oct. 19, 1999), both of which are incorporated herein by reference. The feedback to the patient is via goggles that contain light emitting diodes (LEDs), but may also include sounds. The treatment, via the output of LED's, was accomplished at two different frequencies, but always within a predetermined range of the current actual brain wave frequency and the desired frequency. The apparatus to accomplish this method had a computer processor, a computer memory, EEG electrodes along with an amplifier, a programmable timing generator responsive to the computer processor for generating the two frequencies, audio amplifiers and a beat frequency generator driving a visual frequency amplifier.
It was subsequently discovered that the patient did not need to actually see the LEDs in the goggles for the therapy to have a benefit. The LEDs could be masked or completely blocked and the patient would still show clinical improvement. It was surprisingly discovered that very low electric fields generated by the power to the LEDs in the goggles was therapeutically effective.
This discovery then led to the state of the art Low Energy Neurofeedback System, or LENS, of which an exemplary system for such treatment is shown in FIG. 2. The LENS method employs extremely weak intensities of feedback and does involve the patient's own EEG driving the feedback, but does not involve any conscious participation or even positive intention. The LENS works by continuously monitoring EEG activity and then uses these readings to determine the frequency of very small electromagnetic fields that are “offset” several cycles per second (hertz) faster than the patient's dominant brainwave. LENS uses an electromagnetic field as the carrier wave for the feedback. With this method, the EEG leads serve as bi-directional conduits for both the brainwaves and the feedback signals. This feedback stimulus input is then delivered down electrode wires at generally seven or fewer electrode sites in the course of a treatment session, for only one second per site. This input is much weaker than what the brain receives from holding a cell phone to one's ear, the power being in the range of nano-watts/cm2. The LENS approach is reviewed in the Journal of Neurotherapy, Vol 10, no. 2/3, 2006, pp. 5-39, which is incorporated herein by reference.
In the LENS method either the computer or a microprocessor associated with EEG amplifier performs the calculations based on the EEG and then delivers power to different leads placed on the patient's scalp. The exact order of treatment, power, duration and like parameters depends on the clinical findings, and in particular an initial evaluation of the patient's sensitivity to treatment.
A block diagram of the LENS system is shown in FIG. 2, while the components of microprocessor associated with generating the feedback signal are illustrated in FIG. 3. The EEG Amplifier/microprocessor of FIGS. 2 and 3 that is used to acquire the EEG and provide the feedback stimulus may be acquired from J&J Engineering Incorporated, 22797 Holgar Ct. Nebr., Poulsbo, Wash. 98370, subject to restrictions customary for medical devices. As the microprocessor of FIGS. 2 and 3 is not needed to deploy the current invention it will not be described further. However, it should be appreciated that due to its components and complexity it adds significantly to the expense of the neurofeedback equipment. The software that interfaces with the EEG acquisition system of J & J Engineering for the LENS method is available from OchsLabs, 8151 Elphick Lane, Sebastopol, Calif. 95472, subject to similar restrictions. The software aids in the clinician's diagnosis, treatment plan development and actual treatment based on the LENS protocols, which vary depending on the patient's condition and the reason for treatment, among other factors.
It is a primary object of the present invention to provide a means for LENS treatment that does not require the special microprocessor and associated hardware required to power the EEG leads.